The present invention relates to a steering-wheel arrangement, and more particularly relates to a steering-wheel arrangement which includes an air-bag unit containing an air-bag adapted to be inflated in the event that an accident should occur in order to protect the driver of the vehicle.
It has been proposed previously to provide a steering-wheel arrangement incorporating an air-bag unit. In such a prior proposed arrangement, initially a steering-wheel is fabricated including a rim and spokes connecting the rim to a hub plate. The steering-wheel incorporates mounting points for an air-bag unit. Typically the mounting points are on or near to the hub plate. The air-bag unit is mounted in position by engaging connecting elements provided on the air-bag unit with the mounting points provided on the steering-wheel.
Typically the air-bag unit has an upper cover which, in use, is visible, and when the air-bag unit is mounted in position on the steering-wheel, at least parts of the periphery of the cover are spaced from adjacent parts of the steering-wheel. Typically this may occur in the region of the spokes. It is desired to provide a uniform and even gap between the periphery of the cover and the adjacent parts of the steering-wheel, but it has been found that this may be difficult to achieve when the air-bag unit is mounted in position by mounting elements which are located remote from the periphery of the cover. It is, of course, desirable for the air-bag unit to be mounted securely in position on the steering-wheel, since otherwise, subsequent to inflation of the air-bag, the air-bag unit itself may become disengaged from the steering-wheel due to the substantial forces applied to the air-bag unit during, and at the completion of inflation of the air-bag.
The present invention seeks to provide an improved steering-wheel arrangement.
According to this invention there is provided a steering-wheel arrangement comprising a steering wheel and an air-bag unit to be mounted on the steering-wheel, the steering-wheel incorporating at least one mounting unit, the air-bag unit having a cover with a periphery which, when the air-bag unit is in position on the steering-wheel, lies adjacent one or more fixed parts of the steering-wheel, defining a gap therebetween, the air-bag unit having at least one connecting element, the element being engageable with a respective mounting unit on the steering-wheel, the mounting unit comprising a housing, the housing defining at least one aperture through which a connecting element may be inserted, the housing containing a spring clip to engage part of the connecting element to prevent the connecting element from being withdrawn out of the aperture, and thus to retain the air-bag unit, wherein co-operating locating elements are provided on the air-bag unit and on the steering-wheel, the locating elements being located at least two spaced-apart positions and being distanced from each connecting element by a distance greater than one-third of the minimum distance from the said connecting element to the closest part of the periphery of the cover.
Preferably the locating elements are distanced from the associated connecting element by a distance greater than one-half of the minimum distance from the said connecting element to the closest part of the periphery of the cover.
In a preferred embodiment the locating elements provided on the air-bag unit are located at or adjacent the periphery of the cover.
Consequently the periphery of the cover is provided with a moulding defining an inverted channel, the moulding constituting the locating elements.
Preferably the locating elements provided on the steering-wheel are mounted on locating units mounted on the spokes of the steering-wheel.
In such an embodiment each locating unit may be provided with a locating element in the form of a projection to be received within said channel.
Conveniently at least one of the locating elements is provided with a horn actuating switch.
Preferably two or more connecting elements are provided on the air-bag unit, each engageable with a respective mounting unit on the steering-wheel.
Advantageously the connecting element is dimensioned and configured to have a “floating” connection with the respective mounting unit.
Preferably the spring comprises a spring clip adapted to engage the connecting element on two opposed sides.
Advantageously the connecting element is provided with a groove to receive the spring clip.
Conveniently the spring clip is retained within a tubular housing, the housing presenting two aligned apertures to receive the connecting element, the clip being located between the apertures.
Preferably the spring has at least two degrees of freedom of movement within the housing, and the aperture has a larger dimension than that of the part of the connecting element received in the aperture, so that the connecting element may move within the aperture. The air-bag unit may be mounted on the steering-wheel to provide a complete steering-wheel assembly.